• Title/Summary/Keyword: Temperature changes

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A study on physical characteristics by temperature changes of electro-magnetic clutch installed in electric point machine (전기전철기용 전자클러치의 온도 변화에 따른 물리적 특성에 대한 연구)

  • Shim Jae-Bock;Ohn Jung-Guen;Kwon Ki Jin;Choi Yeng-Ha
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.1259-1265
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    • 2004
  • Electro-magnetic clutch which is affected by elements of electric, magnetic and mechanical friction is important that it has a characteristic changes by environmental impact. Expecially, it is equipped in railroad sideway which is bleak external environment. Therefore, this paper investigated affections by temperature changes, which can make out through physical characteristics such as friction torque, minimum slipping torque, rated slipping torque of electro-magnetic dutch.

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Changes in Quality of Strawberry during Circulation by the Refrigerate Case (냉장화 상자에 의한 딸기의 유통중 품질변화)

  • 박인경;김광수
    • Food Science and Preservation
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    • v.1 no.1
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    • pp.55-60
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    • 1994
  • To invedtigate the effect of refrigerate case on the Quality of strawberry during circulation, the temperature changes on the amounts of dry ice and ice cube were examined. And also, the effect of precooling on the changes in temperature and quality of the fruits were studied. Strawberry precooling-treated at 4$^{\circ}C$ for 24hours was prolonged the shelf-life, and Quality was Progressed.150g of dry-ice Per kg of the strawberry was kept quality. It was prolonged more 2 days than present circulation system.

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A Study on Clothes Sales Forecast System using Weather Information: Focused on S/S Clothes (기상정보를 활용한 의류제품 판매예측 시스템 연구: S/S 시즌 제품을 중심으로)

  • Oh, Jai Ho;Oh, Hee Sun;Choi, Kyung Min
    • Fashion & Textile Research Journal
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    • v.19 no.3
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    • pp.289-295
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    • 2017
  • This study aims to develop clothing sales forecast system using weather information. As the annual temperature variation affects changes in daily sales of seasonal clothes, sales period can be predicted growth, peak and decline period by changes of temperature. From this perspective, we analyzed the correlation between temperature and sales. Moving average method was applied in order to indicate long-term trend of temperature and sales changes. 7-day moving average temperature at the start/end points of the growth, peak, and decline period of S/S clothing sales was calculated as a reference temperature for sales forecast. According to the 2013 data analysis results, when 7-day moving average temperature value becomes $4^{\circ}C$ or higher, the growth period of S/S clothing sales starts. The peak period of S/S clothing sales starts at $17^{\circ}C$, up to the highest temperature. When temperature drops below $21^{\circ}C$ after the peak temperature, the decline period of S/S clothing sales is over. The reference temperature was applied to 2014 temperature data to forecast sales period. Through comparing the forecasted sales periods with the actual sales data, validity of the sales forecast system has been verified. Finally this study proposes 'clothing sales forecast system using weather information' as the method of clothing sales forecast.

Temperature analysis of a long-span suspension bridge based on a time-varying solar radiation model

  • Xia, Qi;Liu, Senlin;Zhang, Jian
    • Smart Structures and Systems
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    • v.25 no.1
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    • pp.23-35
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    • 2020
  • It is important to take into account the thermal behavior in assessing the structural condition of bridges. An effective method of studying the temperature effect of long-span bridges is numerical simulation based on the solar radiation models. This study aims to develop a time-varying solar radiation model which can consider the real-time weather changes, such as a cloud cover. A statistical analysis of the long-term monitoring data is first performed, especially on the temperature data between the south and north anchors of the bridge, to confirm that temperature difference can be used to describe real-time weather changes. Second, a defect in the traditional solar radiation model is detected in the temperature field simulation, whereby the value of the turbidity coefficient tu is subjective and cannot be used to describe the weather changes in real-time. Therefore, a new solar radiation model with modified turbidity coefficient γ is first established on the temperature difference between the south and north anchors. Third, the temperature data of several days are selected for model validation, with the results showing that the simulated temperature distribution is in good agreement with the measured temperature, while the calculated results by the traditional model had minor errors because the turbidity coefficient tu is uncertainty. In addition, the vertical and transverse temperature gradient of a typical cross-section and the temperature distribution of the tower are also studied.

Effect of Dampening Paper, Silica Gel and Temperature Treatment on Change of Flower Color of Dog-tooth Violet (Erythronium japonicum Decne) in Press Flower

  • Yoon Jae-Ho;Song Won-Seob
    • Plant Resources
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    • v.8 no.3
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    • pp.263-274
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    • 2005
  • We have studied the effects of dampening papers (Dampened paper, Newspaper, Korean paper, Flower sheet), silica gel (30g, 60g) and temperature ($20^{\circ}C,\;25^{\circ}C$) on color changes of Erythronium japonicum. In the treatment of $20^{\circ}C$, color changes were low in treatments with silica gel rather than in a treatment of dampening papers. In particular, newspaper and Korean paper showed much less changes in colors by the combination treatments with 30g of silica gel. Likewise, in the treatment of $25^{\circ}C$, color changes were low in combination treatments with silica gel rather than in a alone treatment of dampening papers. For the combination treatment with 30g of silica gel, low color changes were shown in the divisions of newspaper and Korean paper, while for the combination treatment with 60g of silica gel, low color changes were shown in the those of Korean paper and dampened paper.

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Changes of Surface Temperature and Electromyography Activities by Local Heat and Cold (온열과 냉의 국소적용에 의한 체표면 온도와 근전도 활동의 변화)

  • Choi, Seok-Ju;Lim, Sang-Wan;Kim, Su-Hyon;Mun, Dal-Ju
    • Journal of the Korean Academy of Clinical Electrophysiology
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    • v.5 no.2
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    • pp.61-72
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    • 2007
  • INTRODUCTION: Local heat and cold application has been frequently used as means of muscle relaxation and blood circulation or reinforcing muscle strength, relaxing muscle tension in clinical situation. In particular, it has been known that long-term heat and cold application for relaxing muscle tension inhibits muscle spasticity or tension. But, it has been rarely reported that what influences of heat and cold application on activation of muscle action potential. Therefore, this study aims to analyze surface temperature and electromyography activities according to the heat and cold application. METHODE: Subjects of this research were 10 normal men and women (5 men, 5 women). Hot pack and cold pack was applied to vastus medialis muscle of thigh and rectus femoris muscle for 20 min. Surface temperature of vastus medialis muscle and rectus femoris muscle was measured, knee joint of subjects was in $45^{\circ}$ flexion, sitting on a chair, maximal isometric contraction was induced, surface electromyography (sEMG) signals were collected and root mean square (RMS) and median frequency (MOF) were analyzed. All measurements were conducted before and immediately after experiment, 10 min., 20 min. and 30 min. after experiment. Data were analyzed with SPSS 12.0 program, comparison of changes in superficial temperature and sEMG signals through repeated measurement was conducted with repeated measures ANOVA and significance level $\alpha$ was 0.05. RESULTS: Changes of surface temperature of vastus medialis muscle according to cold application were radically decreased immediately after application, but it was recovered after 30 min. of application and it showed significant difference (F4. 36=72.216, P<0.001). Surface temperature of rectus femoris also showed radical decrease immediately after application, but it was recovered after 30 min. of application and showed significant difference (F4. 36=88.930, P<0.001). Changes of surface temperature of vastus medialis muscle according to heat application were radically increased immediately after application, but it was recovered after 30 min. of application and it showed significant difference (F4. 36=27.267, P<0.001). Surface temperature of rectus femoris also showed radical decrease immediately after application, but it was recovered after 30 min. of application and showed significant difference (F4. 36=19.774, P<0.001). Changes of sEMG by heat and cold application were no statistical difference. Surface temperature of skeletal muscle after heat and cold application showed significant change for 30 min., but it was found that increase or decrease of surface temperature had not great influence on sEMG activities.

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COMPARATIVE STUDY ON BODY TEMPERATURE CHANCE OF NEWBORN INFANTS IN GENERAL CRIB AND ELECTRIC-HEAT CRIB (일반침대와 가온침대에 있는 신생아의 체온변화에 관한 비교연구)

  • 박영숙
    • Journal of Korean Academy of Nursing
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    • v.4 no.1
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    • pp.95-106
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    • 1974
  • The Purpose of this study was to observe the body temperature changes of newborn infants in general crib and electric heat crib after birth for the period required to reach the optimum body temperature. Forty-seven newborn infants who were delivered at Seoul National University Hospital during the period from June 12 to September 13, 1973 were chosen as Subjects for this study. The criteria for the choice of subjects were the babies with normal spontaneous delivery; body weight 2.5kg and over at birth; Apgar so ore seven and over and gestation period over thirty-six weeks. Of these subjects, by random sampling thirty-one newborn infants were placed in the general crib and sixteen in the electric-heat crib. The rectal body temperature of these newborn infants were taken and recorded at fifteen-minute interval for the first one hour period after birth, at thirty minute interval for the next two hours and at one hour interval for the remaining period up to eight hours. The results of the study were as follows: 1. The mean body temperature of the newborn infants on admission to nursery ranged from 98.7℉. to 99℉. irrespective of the body weight and the room temperature. 2. There was a significant difference in the body temperature changes of the newborn infants as a total between the general crib and the electric-heat crib from three to eight hours after birth. It was found that the body temperature of the newborn infants in the electric-heat crib was significantly higher than that of the newborn infants in the general crib. 3. In comparison with the body temperature changes of the newborn infants in the general crib, the newborn infants in the electric- heat crib exhibited significantly higher body temperatures in all three body weight groups; from four to eight hours after birth in the 2.5-2.9kg body weight group; from three to seven hours after birth in the 3.0-3.4kg body weight group; from two and half to six hours after birth in the group with body weight over 3.5kg. 4. Time required to reach 98℉. of body temperature was four hours in the 3.5-2.9kg body weight group, three hours in the 3.0-3.4kg. body weight group and two and half hours in the group with body weight over 3.5kg in the electric- heat crib. In the general crib, it took over eight hours in the 2.5-2.9kg body weight group and five hors in both the 3.0-3.4kg and over 3.5kg body weight group to reach 98℉ of body temperature. 5. The lowest mean body temperature of newborn infants in both general and electric- heat crib appeared in forty-five minute after birth and the temperature ranged from 96.4℉ to 96.5℉. 6. The mean body temperature of the newborn infants in the general crib was increased as the room temperature. 7. The body weight, the room temperature and the time elapsed after birth fore proved to be significant factors influencing the body temperature changes of newborn infants. From tile above results, the three hypotheses were positively accepted.

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Delayed Deproteinization Causes Methodological Errors in Amino Acid Levels in Plasma Stored at Room Temperature or -20℃

  • Li, Junyou;Piao, Chunxiang;Jin, Huazi;Wongpanit, Kannika;Manabe, Noboru
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.12
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    • pp.1703-1708
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    • 2009
  • Deproteinization has been recognized as a prerequisite for amino acid analysis of plasma samples. For plasma stored at room temperature, delaying deproteinization for 30, 60 or 120 minutes did not result in significant changes in the mean CV (coefficient of variation), which ranged from 4.4 to 5.6%. However the mean CV of aspartic acid, ${\alpha}$-aminoadipic acid, alanine and lysine was about 10%. When the plasma was stored frozen at -20${^{\circ}C}$, the CV was increased at 0 and 120 minutes after thawing, to 12.4% (range, 4.1 to 35.3%) and 8.0% (2.5 to 30.7%), respectively. The concentrations in plasma during storage at room temperature of all the amino acids analyzed showed significant changes. In plasma stored for 30 minutes at room temperature, 17 amino acids increased in concentrations and two decreased. Extending this period to 60 or 120 minutes increased the instability as compare to the reference group. Storing plasma at -20${^{\circ}C}$ for 2 weeks resulted in significantly greater changes in the amino acid concentrations than at room temperature. On extending the storage time at room temperature, after thawing, to 30, 60, and 120 minutes, 21, 20, and all 22 amino acids respectively changed significantly (p<0.01). The present study indicates that methodological errors occur in the concentrations determined for all amino acids when plasma is left at room temperature. The storage of frozen non-deproteinized plasma accompanied more significant changes in most amino acid concentrations and thus should be avoided. Deproteinization should be performed as soon as possible after plasma collection.

Temperature Changes in Dentin upon Pulsed Nd:YAG Lasing Distance (Pulsed Nd:YAG 레이저 조사거리에 따른 상아질의 온도변화)

  • Jae-Hyung Kim;Woo-Cheon Kee
    • Journal of Oral Medicine and Pain
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    • v.20 no.2
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    • pp.327-334
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    • 1995
  • In order to observe the influence of pulsed Nd:YAG laser at its out-of-contact with dentin on tooth temperature, we have applied pulsed Nd:YAG laser to 2mm thick dentin sample at a point of contact and from a distance of 1mm, 2mm, 3mm and 4mm with an energy of 0.3W, 0.5W, 0.8W, 1.5W and 2.0W. They were exposed to periods of 3 seconds, 6 seconds, 9 seconds and 15 seconds respectively and measured temperature changes. The results as follows : 1. When the time ad intensity of power were constant, the temperature changes on dentin of tooth depended on the distance. The temperature increased when the laser intensity increased bu two other conditions were contact. 2. At the point of contact, the temperature has risen over $5^{\circ}C$ regrdless of intensity of the power or the time. However, there was $5^{\circ}C$ fluctuation with 0.3 W for 3 seconds treatment. 3. The temperature change was less than $5^{\circ}C$ thermal change at the distance of 1mm and 2mm respectively when lased for 3 seconds, 6 seconds, 12 seconds and 15 seconds with 0.3 W. Similar results were observed at 3 and 6 seconds treatment with 0.5 W and at 3 seconds treatment with 0.8 and 1.0W respectively. 4. It showed less than 5(C thermal change when lased for 3 seconds, 6 seconds, 9 seconds, 12 seconds and 15 seconds with 0.3W at the distance of 3mm and 4mm. The same results were seen in 3 seconds, 6 seconds and 9 seconds treatment with 0.5W and in 3 seconds with 0.8W and 1.0W respectively. As we have seen the above, the results has indicated that pulsed Nd:YAG lasing at its off contact on dentin of 2mm thickness will not cause irreversible changes if lasing intensity, lasing distance and lasing time are appropriate.

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Impact of Greenhouse Gas Emissions from Commercial Aircraft on Radiative Forcing and Temperature Change at the Airports in Korea: Comparison between Simplified Expression and Radiative Transfer Model (국내 공항의 항공기 온실가스 배출에 의한 복사강제력 및 기온변화 영향 연구: 배출량에 의한 추정식과 복사전달모델의 비교 분석)

  • Song, Sang-Keun;Shon, Zang-Ho;Jeong, Ju-Hee
    • Journal of Korean Society for Atmospheric Environment
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    • v.30 no.5
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    • pp.411-422
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    • 2014
  • In this study, spatial and temporal variations of radiative forcing (RF) and mean temperature changes due to greenhouse gases ($CO_2$, $CH_4$, and $N_2O$) emitted from commercial aircraft were examined based on the simplified expression at the airports in Korea during 2009~2010. The radiative transfer model (SBDART) was used to compare with the RF and mean temperature changes calculated from the simplified expressions for greenhouse gas $CO_2$. The RF simulated by the SBDART was about 67% higher than that of the simplified expression, on average. The highest mean RF (up to $9.0mW/m^2$ for $CO_2$) and mean temperature changes (up to $9.7{\times}10^{-5}^{\circ}K/day$ for $CO_2$) for all GHGs occurred at Ulsan airport during the study period, whereas the lowest RF and temperature changes at Yangyang (for $CO_2$) and Sacheon airports (for $CH_4$ and $N_2O$). In the case of $CH_4$ and $N_2O$, their effects to the RF and mean temperature change were negligible compared to $CO_2$.